A WATER-COMPATIBLE PHENOLIC HYDROXYL MODIFIED POLYSTYRENE AS AN ADSORBENT FOR ADSORBING PHENOLIC COMPOUNDS FROM AQUEOUS SOLUTIONS

A water-compatible phenolic hydroxyl modified polystyrene adsorbent (AM-1) for adsorbing and removing phenolic compounds from aqueous solutions was prepared by covalent bonding of phenolic hydroxyl groups to the surface of porous polystyrene-divinylbenzene beads, this resin can be used directly without wetting process. A comparison of the sorption properties of the new resin and Amberlite XAD-4 toward four phenolic compounds, phenol, p-cresol, p-chlorophenol, and p-nitrophenol was made. The capacities of equilibrium adsorption of AM-1 for all four phenolic compounds increased around 20% over that of Amberlite XAD-4, which may be contributed to phenol hydroxyl group on the surface and the unusual pore distribution. At their dilute solution, the equilibrium adsorption capacities of AM-1 for phenol increased about 62% over that of Amberlite XAD-4, while equilibrium adsorption capacities of the other three phenolic compounds increased 4-35%, suggesting an advantage of AM-1 over Amberlite XAD-4 in the collection of phenol. Freundlich isotherm equations and isosteric adsorption enthalpies for the four phenolic compounds indicate a physical adsorption process on the Amberlite XAD-4 and AM-1 resins. Column studies for phenol show that AM-1 resin has excellent adsorption and desorption performance.